Super charger components

ABSTRACT

A pulley assembly having a body, a shaft mount and a plurality of bolts is disclosed. The body is aligned to the shaft mount by providing a tight tolerance between a shoulder portion of the bolt and a neck portion of a counter sunk hole formed in the body. Additionally, an outer surface of the body may have a pattern of friction lines or patches formed by fusing particulate matter to the outer surface with heat generated by a laser beam.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of U.S. patentapplication Ser. No. 14/656,556, filed on Mar. 12, 2015, which is acontinuation in part of U.S. patent application Ser. No. 14/213,740,filed on Mar. 14, 2014, the entire content of which is expresslyincorporated herein by reference.

STATEMENT RE: FEDERALLY SPONSORED RESEARCH/DEVELOPMENT

Not Applicable

BACKGROUND

The various embodiments and aspects described herein relate tocomponents for a supercharger of an automobile.

The supercharger has a pulley which is connected to a rotating shaft ofthe engine and drives the supercharger. The pulley has a small diameterwhich leads to slippage between the pulley and the belt driving thepulley.

Accordingly, there is a need in the art for an improved method anddevice for mitigating slippage between the pulley and the belt andaddressing other deficiencies.

BRIEF SUMMARY

The various embodiments and aspects disclosed herein address the needsdiscussed above, discussed below and those that are known in the art.

A pulley assembly having a body, a shaft mount and a plurality of boltsthat attach the body to the shaft mount is disclosed. The shaft mount ismountable to a shaft of a supercharger. The body is attachable to theshaft mount with the bolts. In particular, the shaft mount has aplurality of threaded holes that engage threads of the bolts. The bodyhas a series of counter sunk holes that are aligned to the threadedholes of the shaft mount. The counter sunk holes have a him neck areathat is minimally larger than a shoulder area of the bolt. As such, whenthe bolt is inserted into the counter sunk holes and threaded into thethreaded holes of the shaft mount, the tight tolerancing (i.e., within0.001 inches) between diameters of the necks of the counter sunk holesand the shoulder of the bolts align the body of the pulley assembly tothe shaft mount and ultimately to the shaft of the supercharger. Inanother aspect, the outer surface of the body of the pulley assembly hasa pattern of friction lines for increasing the frictional forces betweenthe outer surface of the body of the pulley assembly and the beltdriving the pulley. The friction lines may be formed by applyingparticulate matter to the outer surface of the body of the pulleyassembly and fusing the applied particulate matter to the outer surfaceby heating the outer surface and the particulate matter. The heat may begenerated by a laser beam that traces a desired pattern of frictionlines. The increased friction mitigates noise by reducing slippagebetween a belt and the pulley. Alternatively, the laser may be used toremove material and to create a rough surface on the outer surface ofthe body of the pulley assembly. The heat generated from the laser beammay trace a desired pattern of friction lines.

More particularly, a pulley for transmitting rotational motion betweenfirst and second rotating shafts with a belt on an automobile engine isdisclosed. The pulley may be fixed to the first rotating shaft. Thepulley comprising a body and a laser infused friction material. The bodymay have a cylindrical central hole for receiving the first rotatingshaft and mounting the body onto the first rotating shaft on theautomobile engine. The cylindrical central hole may define a centralaxis about which the body rotates. The body may have at least one grooveformed circumferentially about the central axis for receiving the belt.The laser infused friction material may be bonded to an outer surface ofthe at least one groove.

The laser infused friction material may be configured into a pattern onthe outer surface of the at least one groove. The pulley may have atleast three grooves. The pulley may have a diameter of about 1-10inches, and more preferably between about 2-4 inches, and even morepreferably about 2.5 inches.

In another aspect, a method of fabricating a pulley for transmittingrotational motion between first and second rotating shafts with a belton an automobile engine is disclosed. The pulley may be fixed to thefirst rotating shaft. The method may comprise the steps of forming abody having a cylindrical central hole for receiving the first rotatingshaft and mounting the body onto the first rotating shaft on theautomobile engine, the cylindrical central hole defining a central axisabout which the body rotates, the body having at least one groove formedcircumferentially about the central axis for receiving the belt;covering an outer surface of the at least one groove with a powdermaterial; and selectively applying heat from a laser beam to the powdermaterial and the outer surface of the at least one groove to fuse thepowder material to the outer surface of the at least one groove. Thefused powder material provides a surface texture to increase itscoefficient of friction and reduce slip with another material such as abelt.

The powder material used in the method may be a formulation sold underthe trademark THERMARK or CERMARK. The powder material used in themethod may also be any powdered metallic material or powdered oxidematerial. By way of example and not limitation, the metallic materialmay be tungsten, various types of carbides, cobalt, titanium, aluminum,steel or combinations thereof. The average size of the of the powderedmaterial may be up to about 100 microns, and is preferably up to about35 microns. More preferably, the powdered material is between about 2-25microns. The texture of the fused material may be increased or decreasedby respectively using larger or smaller sized powdered oxide material.Additionally, ceramic and/or diamond particles may be heterogeneouslymixed in with the powdered metallic material or powdered oxide material.

The powder material and the outer surface of the at least one groove mayreach a temperature of at least 200 degrees Fahrenheit depending on thespecific powder material and the outer surface to fuse the powdermaterial to the outer surface of the groove. By way of example and notlimitation, the powder material may be configured so that the fusingtemperature of the powder material and the outer surface may be as highas about 1,221 degrees Fahrenheit to about 4,566 degrees Fahrenheit foraluminum which are the respective melting and boiling points foraluminum. More broadly speaking, the heat applied to the powder materialand the outer surface is regulated so that the temperature of the outersurface may reach between the melting point and the boiling point of thebase material.

In the method, the covering step may include the step of covering theentire outer surface of the at least one groove.

In the method, the applying step may comprise the steps of mounting thebody to a chuck; mounting the body and the chuck to a laser machine;rotating the body with the chuck while performing the applying heat fromthe laser beam step, rotational motion of the body defining a rotationalaxis; and traversing a head of the laser machine along the rotationalaxis while performing the applying heat from the laser beam step.

In another aspect, a method of removing a pulley from a rotating shaftof an automobile engine is disclosed. The method may comprise the stepsof unscrewing a plurality of first bolts from the pulley to disassemblea first outer body of the pulley from an inner mounting fixture of thepulley; removing the first outer body from the inner mounting fixture;positioning a second outer body over the inner mounting fixture whereinan internal configuration of the second outer body is sized to interfacewith the inner mounting fixture and an external configuration of thesecond outer body is sized to mate with a puller; screwing the pluralityof first bolts or a plurality of second bolts to the pulley to fix thesecond outer body to the inner mounting fixture wherein the second outerbody has a larger flange compared to a flange of the first outer body;engaging the puller to the larger flange of the second outer body; andpulling on the larger flange of the second outer body with the puller toremove the inner mounting fixture from the rotating shaft.

In the method, the larger flange of the second outer body may be locatedon an inner side of the pulley.

In a different aspect, a method for increasing a coefficient of frictionof a surface of a pulley is disclosed. The method may comprise the stepsof disposing a laser machine adjacent to the pulley so that a laser beamof the laser machine is applied to an area of the surface of the pulley;adjusting the laser machine to a roughing setting to emit a laser beamthat vaporizes the surface of the area to increase a roughness of thepulley surface; applying the laser beam of the laser machine onto thepulley surface with the laser machine set to the roughing setting;adjusting the laser machine to a smoothing setting to emit the laserbeam to reduce sharps peaks on the pulley surface caused by the applyingthe laser beam of the laser machine set to the roughing setting; andapplying the laser beam of the laser machine onto the pulley surfacewith the laser machine set to the smoothing setting.

The step of adjusting the laser machine to the smoothing setting fromthe roughing setting may comprise the steps of decreasing a kerf width,decreasing a fill distance and decreasing a power of the laser beam.

The step of adjusting the laser machine to the roughing setting maycomprise the steps of setting a kerf width and setting a fill distanceto be greater than the kerf width. The kerf width may be about between0.0019 and about 0.004 inches. The step of adjusting the laser machineto the smoothing setting may comprise the steps of setting the filldistance to about double the kerf width but can be more or lessdepending on the material being worked on. By way of example and notlimitation, the fill distance may be less than double the kerf width foraluminum and more than double the kerf width for 17-4 stainless steel.

The method may further comprise the step of adjusting the laser machineto an annealing setting to harden the pulley surface.

The method may further comprise the step of rotating the pulley or thelaser machine after performing both applying steps to apply the laserbeam of the laser machine about a circumference of the pulley.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features and advantages of the various embodimentsdisclosed herein will be better understood with respect to the followingdescription and drawings, in which like numbers refer to like partsthroughout, and in which:

FIG. 1 is a perspective view of a pulley assembly mounted on a shaft ofthe supercharger;

FIG. 2 is a cross-sectional exploded view of the pulley assembly shownin FIG. 1;

FIG. 3 is a cross-sectional view of the pulley assembly illustrating abolt that aligns a body of the pulley assembly to a shaft mount of thepulley assembly;

FIG. 4 is a flowchart for forming friction lines on an outer surface ofthe body of the pulley assembly; and

FIG. 5 illustrates a laser beam used to fuse particulate matter on theouter surface of the body of the pulley assembly for forming thefriction lines;

FIG. 6 is a front view of a variable diameter pulley of a continuouslyvariable transmission;

FIG. 7 is a front view of one of first and second parts of the variablediameter pulley individually mounted to a chuck;

FIG. 8 is a front view of one of first and second parts of the variablediameter pulley individually mounted to a chuck in a differentorientation to a laser beam of a laser;

FIG. 9 is a perspective view of the pulley assembly having an outersurface debossed with a laser to increase a coefficient of friction ofthe outer surface;

FIG. 10 is a cross-sectional view of the pulley assembly shown in FIG.9;

FIG. 11 is a top view of the pulley assembly shown in FIG. 9;

FIG. 11A is a top view of a crosshatching pattern formed on an area ofthe outer surface the pulley assembly;

FIG. 11B is a schematic diagram illustrating a pulse width of a laserbeam of the laser;

FIG. 12 is a cross-sectional view of the outer surface illustrating aplurality of kerfs formed by the laser beam of the laser;

FIG. 13 is a graph of temperature as a function of distance as the laserbeam passes over the outer surface of the pulley assembly to anneal theouter surface; and

FIG. 14 is a table of settings of a laser.

DETAILED DESCRIPTION

Referring now to the drawings, a pulley assembly 10 for a supercharger12 is shown. The pulley assembly 10 is mounted to a shaft 14 of thesupercharger 12. The pulley assembly 10 may have three differentcomponents, namely, a shaft mount 16, a body 18 and a plurality of bolts20. The body 18 is mounted to the shaft mount 16 with the plurality ofbolts 20. In particular, each of the bolts 20 may have a shoulder 22having an outer diameter 24 which is smaller than and within 0.001inches of an inner diameter 26 of a neck 54 of a countersunk hole 28formed in the body 18. The shaft mount 16 has a plurality of threadedholes 30 which receive the bolts 20. In this manner, the neck 54 of thebody 18 aligns the body 18 to the shaft mount 16. Additionally, an outersurface 32 of the body 18 may have a plurality of friction lines 34which mitigate slip between the outer surface 32 of the body 18 and abelt being driven by the pulley assembly 10 or driving the pulleyassembly 10. The increased friction mitigates noise by reducing slippagebetween the belt and the pulley assembly 10.

More particularly, referring now to FIG. 2, the pulley assembly 10 ismade up of at least the shaft mount 16, the body 18 and the plurality offasteners or bolts 20. To mount the pulley assembly 10 to the shaft 14of the supercharger 12, the shaft mount 16 is heated to a temperatureabove the temperature of the shaft 14. The inner diameter 36 of the hole38 of the shaft mount 16 is enlarged due to the heat so that the shaftmount 16 may be slid over the shaft 14. When the shaft mount 16 coolsdown, the shaft mount 16 is fixedly secured to the shaft 14 of thesupercharger 12. The inner diameter 36 of the hole 38 of the shaft mount16 is slightly smaller than an outer diameter 40 of the shaft 14 whenthe shaft 14 and the shaft mount 16 are at the same temperature. Theshaft mount 16 compresses on the shaft 14 when the temperature of theshaft mount 16 reaches the temperature of the shaft 14.

The shaft mount 16 may have a flange 42 that extends outwardly around aperiphery of the shaft mount 16. The flange 42 may have a plurality ofthreaded holes 44 symmetrically disposed about a central axis 46. Theflange 42 may have a proximal surface 48 which mates with a distalsurface 50 of the body 18. The body 18 is mounted to the shaft mount 16with the plurality of fasteners 20. The body 18 has a set ofcorresponding countersunk holes 28 that receive the bolts 20. Thesecountersunk holes 28 are aligned in the same pattern as the threadedholes 44 formed in the flange 42 of the shaft mount 16. The body 18 hasan inner cavity 55 which is large enough to receive the shaft mount 16and a portion 53 of the supercharger 12 that holds the shaft 14. Thebody 18 is disposed over the shaft mount 16 and the countersunk holes 28are aligned to the threaded holes 44. Each of the fasteners 20 are theninserted through the countersunk holes 28 and engage to the threadedholes 44 of the shaft mount 16. The fasteners 20 fixedly secure the body18 the shaft mount 16. Also, the interference fit between the hole 38 ofthe shaft mount 16 and the shaft 14 of the supercharger 12 fixedlysecure the shaft mount 16 to the shaft 14.

To align the body 18 to the shaft mount 16, the bolts 20 have a shoulder22 that mates to a neck 54 of the countersunk hole 28 formed in the body18. In particular, referring now to FIG. 3, a cross-sectional view ofthe pulley assembly 10 is shown. The countersunk hole 28 has twodifferent diameters. A first diameter at a neck 54 identified as innerdiameter 26. A second diameter at a countersunk portion 56 identified asinner diameter 58. The inner diameter 58 receives a head 60 of the bolt20. More particularly, the inner diameter 58 is significantly largerthan an outer diameter 62 of the head 60 of the bolt 20. In contrast,the inner diameter 26 of the neck 54 of the threaded hole 28 is onlyminimally larger than an outer diameter 24 of the neck portion 22 of thebolt 20. More particularly, the inner diameter 26 is within 0.001 inchesof the outer diameter 24 of the neck 22 of the bolt 20. As the threads64 of the bolt 20 engage the threads 66 of the threaded hole 30 of theflange 42 of the shaft mount 16, the shoulder 22 of the bolt 20 entersthe neck 54 of the hole 28 of the body 18. Since the inner diameter 26of the hole 28 is within 0.001 inches to the outer diameter 24 of theshoulder 22, the body 18 begins to align to the shaft mount 60 as two ormore bolts 20 engage the threaded holes 44 of the shaft mount 16.

Optionally, to further secure the shaft mount 16 to the shaft 14, theshaft mount 16 may have one or more socket set screws 68 that engage theshaft 14. In particular, the shaft mount 16 may have an extended length.A threaded hole 70 may be formed in the extended length. Preferably, aplurality of threaded holes 70 are symmetrically formed about thecentral axis 46 to maintain rotational balance of the pulley assembly 10during rotation. By way of example and not limitation, threaded holes 70may be placed on opposed sides of the central axis 46. Alternatively,three holes 70 may be disposed 120° apart from each other about thecentral axis 46 or four holes may be disposed 90° apart from each otherabout the central axis 46. After the shaft mount 16 is mounted to theshaft 14, the socket set screws 68 are threaded into the threaded holes70 and engaged to the shaft 14. Preferably, the socket set screws 68have a knurled end to further engage the shaft 14.

To mount the pulley assembly 10 to the shaft 14 of the supercharger 12,the shaft mount 16 (see FIG. 2) is heated to a temperature above thetemperature of the shaft 14 of the supercharger 12. In doing this, theheat enlarges the inner diameter 36 of the shaft mount 16 so that theinner diameter 36 of the shaft mount 16 when heated is greater than theouter diameter 40 of the shaft 14. While the shaft mount 16 is heated toan elevated temperature, the shaft mount 16 is placed over the shaft 14so that the shaft 14 is now disposed within the hole 38 of the shaftmount 16. As the shaft mount 16 cools down, the inner diameter 36 of theshaft mount 16 decreases. When the temperature of the shaft mount 16 isequal to the temperature of the shaft 14, the inner diameter 36 of theshaft mount 16 is equal to the outer diameter 40 of the shaft 14. Sincethe inner diameter 36 of the shaft mount 16 is less than the outerdiameter 40 of the shaft 14 (when the shaft mount 16 and the shaft 14are at the same temperature and the shaft mount 16 is not mounted to theshaft 14), the inner surface defining the inner diameter 36 of the shaftmount 16 compresses upon the outer surface of the shaft 14 when theshaft mount 16 is mounted to the shaft 14 of the supercharger 12.

To further ensure that the shaft mount 16 is retained on the shaft 14,socket set screws 68 may be threaded into the threaded holes 70 formedin the extended length of shaft mount 16. A distal tip of each of thesocket set screws 68 may have knurls to further engage the shaft 14 andmitigate inadvertent movement between the shaft mount 16 and the shaft14.

The body 18 is then disposed over the shaft mount 16 so that the shaftmount 16 is disposed within the cavity 55 of the body 18. The bolts 20are inserted through the countersunk holes 28 of the body 18 andthreadedly engaged to the threaded holes 44 formed in the flange 42 ofthe shaft mount 16. As the bolts 20 are tightened, the neck 54 of thebolts 20 seat into the neck 54 of the body 18. Due to the tighttolerances between the shoulders 22 of the bolts 20 and the necks 54 ofthe countersunk holes 28 of the body 18, the body 18 begins to align tothe shaft mount 16. The user tightens the bolts 20 to securely attachthe body 18 to the shaft mount 16, and in turn, to the shaft 14 of thesupercharger 12.

To remove the pulley assembly 10 from the shaft 14 of the supercharger12, the user loosens the bolts 20 to remove the body 18 from the shaftmount 16. The purpose of removing the body 18 from the shaft mount 16 isto provide the user with access to the socket set screws 68, if used.The user loosens and removes the socket set screws 68 from the shaftmount 16. The user may then reinstall the original body 18 or install asacrificial body 72 (see FIG. 2). The sacrificial body 72 mayincorporate the counter sunk holes 28 and an enlarged distal flange 74.The enlarged distal flange 74 is used to pull the body 18 and shaftmount 16 off of the shaft 14. The user may then pull the pulley assembly10 from the shaft 14 with the puller.

Referring back to FIG. 1, the body 18 of the pulley assembly 10 may havean outer surface 32. The outer surface 32 may have a plurality ofgrooves 76 circumscribing the body 18 about the rotational axis 46. Inthe embodiment shown in the figures, the pulley assembly 10 has aplurality of grooves. However, it is also contemplated that the variousaspects described herein may be applied to a pulley have a single grooveor a pulley or tensioner having a cylindrical surface. The outer surface32, and in this instance, the grooves 76 engage a belt that wraps aroundthe body 18 and fits within the grooves 76. The outer surface 32 of thebody 18 may be smooth so that during use, the belt wrapped around thebody 18 may inadvertently slip so that the linear speed of the outersurface 32 of the body 18 is not equal to the linear speed of the beltdriving or driven by the pulley assembly 10. To mitigate slippagebetween the belt and the outer surface 32 of the body 18, frictionpatches or lines 34 may be formed on the outer surface 32 of the body18.

In particular, referring now to FIGS. 4 and 5, particulate matter orsubstance may be fused to the outer surface 32 of the body 18 and have acoefficient of friction with the belt greater than the coefficient offriction between the smooth outer surface 32 of the body 18 and thebelt. The particulate matter may be coated over the outer surface 32. Alaser beam 78 of the laser 80 may be directed to selective locations onthe outer surface 32 of the body 18 to fuse the particulate matter tothe outer surface 32 of the body 18. Preferably, the particulate matterwhen fused to the outer surface 32 has a coefficient of friction withthe belt greater than the coefficient of friction between the smoothouter surface 32 of the body 18 and the belt. Moreover, the particulatematter provides a slight raised surface so that the edges of thefriction lines 38 create additional friction between the friction lines34 and the belt. The fusing of the particulate matter to the outersurface 32 of the body 18 is a physical bonding process wherein theparticulate matter is heated and permanently bonded to the outer surface32 of the body 18.

To coat the particulate matter onto the outer surface 32 of the body 18,the particulate matter is applied 82 (see FIG. 4) to the outer surface32 of the body 18. The particulate matter may be applied 82 to the outersurface 32 of the body 18 either by way of an aerosol 100 or airbrushing102. If the particulate matter is delivered or coated onto the outersurface 32 of the body 18 with an aerosol 100, the aerosol can 100 ispurchased in a prepackaged form. The user sprays the entire outersurface 32 of the body 18, and more particularly, sprays the grooves 76.If the particulate matter is delivered or coated onto the outer surface32 of the body 18 by way of airbrushing 102, the particulate matter ismixed with denatured alcohol then sprayed on the outer surface 32 with asprayer. Two types of particulate matter may be utilized when airbrushing. A first type is one sold under the trademark Thermark. Asecond type is one sold under the trademark Cernark. For low productionruns, the Thermark particulate matter is preferred since un-fusedparticulate matter on the outer surface 32 is easily removed by wipingwith a damp wet rag. However, for large production runs, Cernark ispreferred since the particulate matter may be applied to the outersurface 32 of the body 18 and stored for an extended period of time.

If Thermark is used, then the user applies the particulate mattershortly before fusing 82 the particulate matter to the outer surface 32of the body 18. If Cermark is used, then the user may optionally store84 the coated bodies 18 in storage for an extended period of time. Whendesired, the user takes the coated bodies 18 out of storage and fuses 82the particulate matter to the outer surface 32 of the body 18.Regardless of whether Thermark or Cermark is utilized, the particulatematter may be fused 82 to the outer surface 32 of the body 18 with alaser beam 78. The laser beam 78 heats up the particulate matter and theouter surface 32 of the body 18. The heat permanently attaches theparticulate matter to the outer surface 32 of the body 18 so that theparticulate matter does not rub off as the belt rims over the outersurface 32 of the body 18.

Generally, the particular matter may be provided as a powder. The powdermay be delivered by aerosol or a spray gun. The material of the powdermay be a metallic material. More particularly, the powder may be anyform of a metallic oxide material. By way of example and not limitation,the metallic material may be tungsten, carbides (e.g., tungsten carbide,titanium carbide, silicon carbide, carbide.c++, calcium carbide, boroncarbide), cobalt, titanium, aluminum, steel or combinations thereof. Theaverage size of the of the powdered material may be up to about 100microns, and is preferably up to about 35 microns with a minimum sizebeing 2 microns. The texture of the fused material may be increased ordecreased by respectively using larger or smaller sized powdered oxidematerial. During tests, a powder metallic oxide material having a sizeof about 35 microns has created a 0.007 inch texture to the outersurface 32.

To form the friction lines or patches 34, the body 18 may be attached toa chuck 86 after applying the particulate matter to the outer surface32. The chuck 86 may have a plurality of arms 88 with serrated teeth.The plurality of arms 88 may be inserted within the internal cavity 55of the body 18 and expanded outward. Upon outward expansion, the arms 88automatically center the body 18 onto the chuck 86. The chuck 86 and thebody 18 are placed on a rotary table or an indexer that controls therotational movement 90 of the chuck 86 and the body 18 about rotationalaxis 46. The laser 80 is capable of traversing longitudinally along thecentral or rotational axis 46 in the direction of arrows 92, 94.Preferably, the laser beam 78 of the laser 80 intersects and isperpendicular to the central or rotational axis 46. Additionally, thelaser 80 may be a direct beam laser 80.

The laser beam 78 may be traversed longitudinally along the axis 46 andsimultaneously, the body 18 may be rotated about axis 46 so that thelaser beam 78 traces the pattern of lines, circles, curves, patches andother shapes to form a mark, word, pattern on the outer surface 32 ofthe grooves of the body 18. In FIG. 1, the friction lines 34 are shownas being linear along the longitudinal length of the central axis 46.However, other types of patterns and shapes are also contemplated.

After fusing 82, the particulate matter to the outer surface 32 of thebody 18, the excess particulate matter which is not fused to the outersurface 32 of the body 18 may be removed 96 and reclaimed 98 forsubsequent use. More particularly, the body 18 may be placed in a washtank such as an ultrasonic tank. Fluid within the ultrasonic tank isheated up to 200° F. and the tank is vibrated. The fluid is run througha filter and the particulate matter that was not fused to the body 18 isreclaimed 98 and reused at a later time.

The direct beam laser 80 produces a laser beam 78 having a focal depth104. Preferably, the focal depth 104 is greater than a distance 106between a peek 108 and valley 110 of the grooves 76 formed in the body18. The laser 80 and laser beam 78 are positioned so that the focaldepth 104 covers the entire distance 106. By way of example and notlimitation, the focal depth 104 of the laser beam 78 may be about 0.200inches. In this manner, the laser beam 78 heats up the particulatematter and the surface 32 along the entire height of the grooves 76 toprovide optimal friction lines 34.

It is also contemplated that the process of forming the friction lines34 as discussed above and in relation to FIGS. 4 and 5 may be repeatedover existing friction lines 34 as shown by process line 112 (see FIG.4). In particular, after fusing 82, the particulate matter to thesurface 32 of the body 18, additional particulate matter may be applied82 to the outer surface 32 of the body 18. The additional particulatematter may be fused 82 to the layer of fused particulate matter and tothe bare metal of the body 18. The process may be repeated to increasethe thickness of the layers of particulate matter on the outer surface32 of the body 18.

Other types of lasers 80 may also be utilized to fuse 82 the particulatematter to the outer surface 32 of the body 18. By way of example and notlimitation, a Galvo laser which utilizes one or more lenses to positionthe laser beam 78 on the outer surface 32 of the body 18 may beutilized. In this manner, the throughput is higher than a direct laserbeam 78 or a CO2 laser beam in that the lenses can create multiplefriction lines 34 in one pass.

The process of forming the friction lines 34 is discussed in relation toFIGS. 4 and 5 with the process of producing an emboss on the outersurface 32 of the body 18. However, it is also contemplated that adeboss may be formed on the outer surface 32 of the body 18 by removingmaterial. In particular, the Galvo laser may be utilized to removematerial from the outer surface 32 of the body 18. The Galvo laserutilizes one or more lenses to redirect the laser beam 78 instead ofmoving the laser head 80 to position the laser beam 78 on the outersurface 32 of the body 18.

In addition to forming the deboss on the outer surface 32 with the laser80, it is also contemplated that the deboss may be formed with a microend mill. Regardless of whether the deboss is formed with a laser 80 ora micro end mill, the body 18 is mounted to the chuck 86. The chuck 86and the body 18 are mounted to an indexer or a rotary table whichcontrols the rotational angle of the body 18 as the micro end mill orthe laser 80 removes material from the outer surface 32 of the body 18.In another aspect, it is also contemplated that the body 18 may remainstationary while the micro end mill or the laser 80 both rotate aboutthe body 18 and also traverse longitudinally along the axis 46.

The friction lines or patches 34 were described as being formed on arotary table or indexer that is coordinated with the laser. However, itis also contemplated that the friction lines or patches 34 may be formedmanually. By way of example and not limitation, the part could bemounted to a chuck or a holding mechanism that the user may move byhand.

In another aspect, referring now to FIG. 6, the friction lines orpatches may be formed on other types of pulleys, and also on tensioningrollers having a cylindrical flat surface. By way of example and notlimitation, the friction lines or patches 34 may be formed on innersurfaces 118 of first and second parts 120, 122 of a variable diameterpulley 124 of a continuously variable transmission. When the belt 126 iscloser to the rotational axis 128, the revolutions per minute of thepulley 124 is higher than when the belt 126 is further away from therotational axis 128.

Referring now to FIG. 7, to form the friction lines or patches 34 on theinner surface 118, the first and second parts may each be individuallymounted to the chuck 86. The part 120 or 122 is positioned with theinner surface 118 perpendicular to the laser beam 78. The form the patchor lines 34, the laser 80 is traversed laterally in the direction ofarrows 92 and 94 and the chuck 86 is rotated in direction of arrow 90about rotating axis 46.

Referring now to FIG. 8, a different set up between the part 120, 122and the laser beam 78 is shown. Instead of the part 120, 122 beingoriented so that the laser beam 78 is perpendicular to the inner surface118, the inner surface 118 may be oriented at a skewed angle withrespect to the laser beam 78. In FIG. 8, the rotational axis of the part120, 122 is set up so as to be perpendicular to the laser beam 78. Sincethe laser beam 78 has a particular focal depth 104 which is the locationof the laser beam effective for heating up the particular matter and theinner surface 118 to fuse the two together, the laser 80 cannot simplybe laterally traversed in a linear as shown in FIG. 7 if the angle ofthe inner surface 118 is too large so that the entire surface 118 iswithin the focal depth 104 of the laser beam. If the laser is moved tothe left 94 or right 92, the laser beam 78 is effective at fusing theparticulate matter to the inner surface 118 as long as the inner surface118 is within the focal depth of the laser beam. Right before the innersurface 118 comes out of the focal depth of the laser beam 78, the lasermay be traversed up 128 or down 130 to reposition the focal depth of thelaser beam on the inner surface 118. To form the friction lines orpatches 34, the laser 80 is traversed sideways 92, 94 and vertically128, 130 in a staggered fashion. This technique can also be used forpulleys that have a deep groove wherein the distance 106 between thepeak 108 and the valley 110 of the deep groove is greater than the focaldepth 104 of the laser beam 78.

Referring now the FIGS. 9-13, a method and apparatus for forming thedeboss on the outer surface 32 of the body 18 in order to increase acoefficient of friction of the outer surface 13 of the body 18 is shown.In particular, the laser beam 78 of the laser 80 may create a pluralityof kerfs 150 (see FIG. 12). These kerfs 150 form the deboss on the outersurface 32 of the body 18. This is accomplished with a roughing pass ofthe laser beam 78 on the outer surface 32 of the body 18. Additionalpasses of the laser beam 78 on the outer surface 32 of the body 18 maybe made for different purposes. These additional passes may be asmoothing pass wherein excessively sharp protrusions formed during theroughing pass are rounded out or knocked down and an annealing passwhich raises the temperature of the surface 32 of the body 18 in orderto harden the outer surface 32 of the body 18 and/or recast material 166formed during the roughing pass. More particularly, the laser 80 mayperform 1) the roughing pass, 2) smoothing pass, 3) the roughing andsmoothing passes, 4) the roughing, smoothing and annealing passes or 5)the annealing pass on the outer surface 32 of the body 18.

As shown in FIG. 9, the laser 80 is disposed above the body 18 havingthe surface 32 on which the deboss which increases the coefficient offriction is to be formed. A direction of the laser beam 78 can becontrolled by lenses and mirrors in order to cover an area 152 of theouter surface 32 of the body 18. Due to the curvature of the outersurface 32, cannot cover the entire outer surface 32 of the body 18. Thebody 18 may be rotated about central axis 46 or the laser 80 may berotated about the body 18 with respect to the central axis 46 in orderto deboss the entire circumference of the body 18. Preferably, the body18 and the laser 80 are stationary while the laser beam 78 is performingone or more of the roughing pass, smoothing pass and annealing pass onthe area 152 being worked on by the laser beam 78 of the laser 80. Afterthe laser beam 78 works the area 152 with one or more of the roughingpass, smoothing pass and annealing pass, either the laser 80 and/or thebody 18 rotates so that the laser beam 78 can work one or more of thepasses on a different area 152 on the circumference of the outer surface32 of the body 18.

Referring now to FIG. 10, a cross-sectional view of the body 18 shown inFIG. 9 with respect to the laser 80 is shown. Preferably, the laser beam78 is centrally aligned to the central axis 46 of the body 18 in thatthe laser beam 78 is not skewed. The laser beam 78 may be skewed to theleft or right as shown in dashed lines 154, 156 as well as along alength of the central axis 46. Theoretically, the laser beam 78 may beskewed to the left 154 or right 156 so that the laser beam 78 is tangentto the left and right sides of the body 18. However, at such anexcessive skewed angle, the power of the laser beam 78 is less ornon-effective. As such, the laser beam 78 is skewed to the left andright 154, 156 to a smaller angle 158 so that the focal depth or depthof field 164 of the laser beam 78 coincides with or encompasses theouter surface 32 of the body 18 at a valley 160 and peak 162 of a grooveformed on the body 18. The body 18 shown in FIGS. 9-11 is that of apulley having a plurality of grooves that define the valley and peaks160, 162. However, the method and apparatus for forming the deboss maybe used on a variety of other surfaces including but not limited to apulley having a single groove such as one that is incorporated into acontinuously variable transmission (CVT) or a flat idler pulley. Morebroadly speaking, the method and apparatus for forming the deboss may beused on any surface that contacts a belt or requires an increasedcoefficient of friction. Likewise, the laser beam 78 is skewed to theleft and right 164, 156 to a smaller angle 158 so that the focal depthor depth of field 164 of the laser beam 78 coincides with andencompasses the outer surface 32 of the body 18. For the flat idlerpulley, there are no valleys and peaks. As such, the curvature of thepulley is accounted for in determining the acceptable angle 158. For aCVT, the laser beam 78 may be applied to the surface 118 by forming thedeboss on the first and second parts 120, 122 separately as discussedabove during the emboss process. In particular, the laser debosses thefirst part and the second part separately which are then assembledtogether at a later time.

Referring now the FIG. 11A, a top view of the area 152 which is workedby the laser beam 78 of the laser 80 is shown. In this regard, the laserbeam creates a series of straight line dashes at an angle 172 withrespect to the central axis 46 of the body 18. In FIG. 11A, the groovesof the pulley are not shown for clarity. Also, FIG. 11A is a top view ofonly the area 152 worked by the laser beam 78 of the laser 80. The laserbeam 78 can be adjusted to pass over the area 152 at different angles.By way of example and not limitation, the preferred angles are 0° 30°,45°, 60°, 90°, 120°, 125°, 150°. These angles are known as thecrosshatching angles 172. The laser beam 78 of the laser machine 80creates a series of parallel short line dashes. A distance between theshort line dashes is referred to as a crosshatching size 174 (see FIG.12). The laser beam 78 may be adjusted to run at a particular speedmeasured in inches per second.

Referring now to FIG. 12, the laser 80 is shown emitting a laser beam 78onto the outer surface 32 the body 18. The laser beam 78 vaporizes theouter surface 32 in order to create an indentation or a kerf 150. Thisis the deboss formed by the laser beam 78. When the laser beam 78vaporizes a portion of the outer surface 32 of the body 18, recastmaterial 166 lines an interior of the kerf 150 and also extends outwardabove the outer surface 32 of the body 18. The outward extensions areshown by peaks 168 of the recast material 166. The kerf 150 is definedby a width 170 at the peaks 168. It is also contemplated that the kerfwidth 170 may be measured at the outer surface 32 including the recastmaterial 166 as shown by dimension line 170 a. The kerfs 150 are shownin FIG. 12 as being formed vertically straight up-and-down. However, thelaser 80 from the position shown in FIG. 12 emits the laser beam 78 at askewed angle. The first kerf 150 would not be formed straightup-and-down. The drawing is shown in this fashion in FIG. 12 because thedrawing is not to scale since the distance between the laser 80 and theouter surface 32 and the distance 174 between kerfs 150 are not toscale. In actuality, the distance 174 is measured in thousandths of aninch whereas the distance between the laser 80 and the surface 32 ismeasured in inches if not feet.

Referring now to FIG. 11B, a length of the kerf 150 and a gap betweenkerfs 150 may be defined by a pulse width 178 and a speed of the laserbeam 78 which are adjusted on the laser 80. The pulse width 178 isdefined by a length of time that the laser 80 is generating the laserbeam 78 over a period 180 of fixed time. Laser beams 78 pulse at regularintervals. The pulses are defined by the period 180 of fixed time. Thepulse width 178 of the laser beam 78 and the linear speed of the laserbeam 78 on the surface 32 defines a length of the kerf 150. After thelaser 80 is turned off so that no laser beam 78 is emitted from thelaser 80, the laser 80 is turned back on after the period 180 of fixedtime from the beginning 182 of the prior pulse width 178. This definesthe gap between kerfs 150.

The laser 80 may be rated at a particular wattage. By way of example andnot limitation, the laser 80 may be a 70 watt laser 80.

Referring now to the chart below, the laser 80 may be adjusteddifferently for each of the roughing pass, smoothing pass and annealingpass. When the laser 80 makes the roughing pass, the laser 80 is set tothe roughing setting shown below. In this regard, the roughing settingmay create a plurality of kerfs 150 having a kerf width 170 betweenabout 0.004 inches and about 0.0021 inches. The laser beam 80 may passover the area 152 two times. During the first pass, the laser beam 78may have a crosshatching angle 172 of about 45°. During the second pass,the laser beam 78 may have a crosshatching angle 172 of about 180°. Thelaser beam 78 runs parallel with respect to the central axis 46 of thebody 18. The laser 80 may be set at 90% power for a 70 watt laser 80.The pulse width 178 of the laser beam 78 may be set to 420 ns. The laserbeam 78 travels on the surface 32 of the body 18 at around 80 inches persecond during the roughing pass. The roughing pass creates a pluralityof kerfs 150 and projects the recast material 166 upward to form peaks168. The setting for the roughing pass may be set so as to create anaggressive texture in that the peaks 168 may tear a belt running on thepulley during use of the pulley. As such, the roughing pass may befollowed up with a smoothing pass.

TABLE 1 Settings of laser machine for 17-4 stainless steel RoughingSmoothing Annealing Stainless steel setting setting Setting Kerf widthin- 0.004 inches 0.0038 inches 0.0026 inches cluding recast materialKerf width not About .0021 About .0022 About .0019 including recastinches inches inches Cross hatching 45/180 degrees 45 degrees 45 degreesangles (parallel lines to fill an area, 180 degrees, 90 degrees, 45degrees and 120 degrees. (Option of outlining area)) Size of cross Min.distance Smaller Greater hatching between parallel lines than kerf thankerf is greater than the width of the width of kerf width of theroughing annealing roughing setting setting setting plus 0.0005 inchesto 0.004 inches (preferably, 0.004 inches or double the kerf width for akerf width of 0.002 inches) Power of machine 90% of 70 watt 90% of 55%of and % wattage 70 watt 70 watt Pulse width 420 nanoseconds 200 30 (34waveform) nanoseconds nanoseconds (2 waveform) (22 waveform) Speed 80inches per 60 inches per 35 inches per second second second

The smoothing pass rounds out the peaks 168 of the recast material 166.In order to do so, the kerf width 170 is set to be smaller than the kerfwidth 170 during the roughing pass. In our example, the kerf width 170for the smoothing pass is set to be about equal to the kerf width 170during the roughing pass. The crosshatching angle 172 is set to thecrosshatching angle 172 of the roughing pass. In our example, theroughing pass had two different crosshatching angles 172. Thecrosshatching angle 172 during the smoothing pass may be set to eitherone of the crosshatching angles 172 used during the roughing pass. Thedistance 174 of the crosshatching may be smaller than the kerf width 170of the roughing pass. The reason is that the laser beam 78 during thesmoothing pass needs to hit a significant amount of peaks 168 to roundout or knock down the peaks 168. In order to account for anymisalignment between the laser beam 78 and the kerfs 150 made during theroughing pass, reducing the crosshatching size 174 to be smaller thanthe kerf width 170 of the roughing pass enables the laser 80 to roundout a significant portion (i.e., more than 25%, 50% or 75%) of the peaks168 of the recast material 166. The smoothing pass is not meant togenerate new indentations in the surface 32 of the body 18. Rather, thesmoothing pass is designed to round off the peaks 168 of the recastmaterial 166. In this regard, the pulse width is significantly reducedso that less energy is introduced into the surface 32 of the body 18.Also, the speed of the laser is reduced in order to ensure that asignificant portion of the peaks 168 generated during the roughing passare rounded out or knocked down.

After the roughing and smoothing passes, it is also contemplated thatthe surface 32 may be annealed by adjusting the laser 80 with theannealing setting shown above. The annealing pass may also be used toadd color to the exterior surface. In annealing the surface 32 of thebody 18, the annealing takes place on the surface 32 of the body 18 to adepth of about a few thousandths of an inch below its exterior.Referring now to FIG. 13, as the laser beam 78 passes over the outersurface 32 of the body 18, the laser beam 78 introduces heat into theouter surface 32 of the body 18. The center of the laser 78 introducesthe most amount of energy into the outer surface 32 of the body 18. Assuch, this position increases the temperature of the outer surface 32the greatest amount. As one measures the temperature going away fromthat position on the surface 32, the temperature of the surface 32decreases as shown in FIG. 13. When the laser beam 78 creates a hatchingpattern, the laser beam 78 forms a series of parallel lines separated bydistance 174. In particular, the laser beam 78 introduces heat into theouter surface adjacent to a first line and raises the temperature of theouter surface 32 in the same manner as before. However, there may be aslight overlap 184 so that the heat introduced into the outer surface 32by the first line may be additive to the heat introduced into the outersurface 32 by the second line. The dashed line 186 shows the temperaturefluctuation on the outer surface. The annealing settings on the laser 80are set so that the temperature of the outer surface remains within anarrow band 188 sufficient to raise the temperature of the outer surface32 to anneal or harden the outer surface 32 on the area 152 thereof orcreate a consistent discoloration thereof. The temperature range toanneal the outer surface for 17-4 stainless steel may be about 800degrees Fahrenheit to about 1500 degrees Fahrenheit, and more preferablybetween about 900 degrees Fahrenheit to about 1150 degrees Fahrenheit.

The various settings described herein were for 17-4 stainless steel.However, the general principles of forming the roughing setting,smoothing setting and the annealing settings may be applied to othertypes of metallic materials such as aluminum, carbon steel, etc. withdifferent settings per their own material characteristics. The settingsare for a model 70W_EP_Z from SPI Lasers, LLC. FIG. 14 is a table ofsettings for 17-4 stainless steel and aluminum. The table illustrates aslightly different setting for 17-4 stainless steel compared to thechart above in that the smoothing pass may be accomplished with twopasses instead of one pass as discussed above. The table in FIG. 14illustrates two different settings for aluminum. The first setting setsthe laser so that the aluminum material is in a sense micro machinedwith a slight recast material protruding upward, whereas the secondsetting sets the laser to have more recast material protrude upwardcompared to the first setting. The first and second settings mayillustrate a range of settings for aluminum.

The various aspects described herein are in relation to the formation ofan emboss and deboss of a textured surface on a surface of a pulleyhaving a plurality of grooves wherein the pulley grooves engage a beltin order to transmit power from a first shaft upon which the pulley ismounted to a second shaft generally parallel to the first shaft.Moreover, the various aspects described herein for the emboss and debossof a textured surface have also been described in relation to formingthe embossed/debossed textured surface on pulleys of a continuouslyvariable transmission or CVT. The embossed/debossed textured surface isformed on first and second parts of a pulley of the CVT, and moreparticularly on a gripping surface which is where the belt engages fortransmitting power between the first and second shafts. More broadly, itis also contemplated that the method and apparatus for forming theemboss or debossed textured surface may be applied to other applicationsincluding but not limited to the following applicational uses. Theembossed or debossed textured surface may be formed on a pulley having ahelical groove or a straight or helical gear, flat cylindrical pulley,etc. By way of example and not limitation, a drum may have a pluralityof belts mounted thereto for transmitting power to or from the drum to asecond shaft. The embossed or debossed textured surface may be formed onthe drum where the drum engages the belt. The embossed or debossedtextured surface may also be formed on a spindle of a lathe. Broadlyspeaking the embossed or debossed textured surface may be formedutilizing the method and apparatus as described herein on a surface thatis used to engage a belt or other power transmission means to increasethe coefficient of friction of the surface in order to prevent slippagebetween the power transmission means and the surface.

The above description is given by way of example, and not limitation.Given the above disclosure, one skilled in the art could devisevariations that are within the scope and spirit of the inventiondisclosed herein, including usage of other types of lasers. Further, thevarious features of the embodiments disclosed herein can be used alone,or in varying combinations with each other and are not intended to belimited to the specific combination described herein. Thus, the scope ofthe claims is not to be limited by the illustrated embodiments.

What is claimed is:
 1. A pulley for transmitting rotational motionbetween first and second rotating shafts of a continuously variabletransmission with a belt, the pulley being fixed to the first rotatingshaft, the pulley comprising: first and second parts being traversablecloser to or further away from each other, each of the first and secondparts mounted onto the first rotating shaft of the continuously variabletransmission, each of the first and second parts having a skewed surfacewhich interfaces with the belt and collectively forms a groove, a laserinduced friction surface applied to a portion of the skewed surfaces ofthe first and second parts which engage the belt during operation of thecontinuously variable transmission, the first and second partsfabricated from a metallic material; and the laser induced frictionsurface applied solely to the skewed surfaces of the first and secondparts.
 2. The pulley of claim 1 wherein a diameter of the pulley isbetween about 2-4 inches in diameter.
 3. The pulley of claim 1 whereinthe laser induced friction surface is a friction material laser infusedto the skewed surfaces of the first and second parts.
 4. The pulley ofclaim 1 wherein the laser induced friction surface is formed with alaser material removal process applied to the skewed surfaces of thefirst and second parts.
 5. The pulley of claim 1 wherein the laserinduced friction surface is formed by a laser to form pits in the skewedsurfaces.
 6. The pulley of claim 3 wherein the friction material isconfigured into a pattern on the skewed surfaces of the first and secondparts.
 7. The pulley of claim 3 wherein the friction material is apowdered material has an average size of between 20-100 microns.